Donkey Konga

Umm... don't you have something like FreeLoader in the US? Play the Freeloader disc, open the lid, insert disc from any region, play game. Easy, no mods.

Hey, if the one we use over here works I've even got a spare one I can send you.

(just checked, according the interweb it will work for you - all you need is a memory card specific to country of origin)

Is this game even nearly as good as Samba De Amigo?

aldo, intriguing... are there any other good jp games?

...that we need to get

I got a Freeloader to play Winning Eleven 7 (released as PES4 elsewhere in the world on other consoles) - you don't get a huge amount out of the depth of the game unless you know how PES works, but you do get to play the best football game made, with the best controller and the best graphics.

Strangely, I've never looked into jp games to see which other ones I might want. Scared of getting addicted to them, possibly. Although I can see looking into it being a way of passing today...